Defining the Neurobiology of Insanity

Defining the Neurobiology of Insanity: Law, Science, and the I-function Reconciled

During the last week or so of class, after a semester of being teased with glimpses of, allusions to, and deferred explanations for the I-function, we at last came face to face with this previously elusive property of the nervous system which allows us to experience experience. The detour was necessary, for it corrected the general misconception that something like an I-function encompasses everything that makes one an individual and defines one's unique personality; it demonstrated the true importance of "the rest" of the nervous system. Indeed, we were shown how the I-function is, in some ways, superfluous, in that it is not necessary for survival. Not to downplay it, however, the I-function is key to understanding what makes us (human beings) what we are, to distinguishing our experience of the world from that of other species. It allows us to conceive of ourselves (our selves) as objects and to perform such behaviors as planning, dreaming, in short, imagining ourselves in situations other than the one in which we 'really' are.

The last few classes were dedicated to addressing issues which still troubled the majority of the class, such as choice and the supernatural; I, however, found my self wondering about another issue, which no one had yet brought up: insanity. What does it mean to insane? What are the (if any) criteria which determine whether or not a person is sane? Are they reflected in said individual's neurobiological make-up? And finally, how does insanity relate to the I-function? As it turns out, research related to these issues is fairly recent, but increasing rapidly, thanks to technological advances and important contributions from several fields in the neurosciences. My goal here is to report on the answers I was able to find to my questions, as well as to ponder the questions raised by these and foreseeable answers.

As might be expected, the term "insanity" has no neurobiological definition and, as a concept in everyday language, is extremely broad and vaguely defined. Not surprisingly, therefore, it is a concept which is neither used nor useful to professionals in the neurosciences, who regard so-called "insane" behaviors as the results of abnormalities or changes within the brain: "...a rough medical translation would be 'psychosis-that is, the more severe kinds of mental illness, involving hallucinations or delusions," (1). In searching for a working criteria of insanity, the closest I came to a formal definition was the criteria used in law to determine whether or not a defendant could be absolved of responsibility for his or her crime.